March 5 (Bloomberg) -- A group of potentially fatal germs
that are difficult to treat because they resist antibiotics are
becoming more of a threat, according to a U.S. report.

About 4 percent of U.S. hospitals and 18 percent of long-term acute care hospitals, such as those that provide
ventilation and wound care, had an infection from carbapenem-resistant Enterobacteriaceae, in the first half of 2012,
according to a report released today by the Atlanta-based
Centers for Disease Control and Prevention.

This family of germs includes organisms such as Klebsiella
and E. coli. Healthy people usually don’t get infected from
these germs. Instead, people who are being treated for other
illnesses, including those on breathing machines, or who have
catheters inserted, are at risk, the agency said. These bugs are
resistant to most antibiotics and contribute to the deaths of as
many as half of the patients who become infected, the CDC said.

“CRE are nightmare bacteria,” Thomas Frieden, CDC
director, said in a call with reporters. “They’re resistant to
all or nearly all antibiotics, they have high mortality rates,
and can spread their resistance to other bacteria. We only have
a limited opportunity to prevent this from spreading to the
community and more organisms.”

Though the resistant bugs are still fairly rare, the
proportion of infections that were most dangerous increased to
4.2 percent in 2011, from 1.2 percent in 2001 in two of the
surveillance systems used to track the bacteria. Most of that
increase was in the Klebsiella species, which can cause
pneumonia, bloodstream infections and meningitis.

Digestive System

The bacteria belong to a family that normally lives in the
digestive system. They can cause infections in other places in
the body, such as the bladder or blood, according to the CDC.
Some of them are resistant even to the antibiotics of last
resort, called carbapenems.

What’s worse, Frieden said, is that the CRE germs can
easily swap genes with other bugs, creating new untreatable
bacteria. While new antibiotics are under development for these
germs, they are in early stages and “not likely to be available
soon,” according to the CDC report.

To prevent the germs from spreading from hospitals into the
community at large, the CDC recommends testing for CRE and
keeping patients with the infection in specialized wards with
dedicated staff. Handwashing among hospital staff is
particularly important, Frieden said. Temporary medical devices
such as catheters should be removed as soon as possible, and
antibiotics should be prescribed wisely.

Unlike methicillin-resistant staphylococcus aureus or MRSA,
CRE may not respond to any antibiotics. CRE infections aren’t as
widespread as MRSA, which escaped the hospital setting.

CRE is “not as widespread, and it’s important we keep it
that way, because it’s so dangerous in terms of high fatality
rate, limited treatment options and ease of spreading,” Frieden
said. “The sooner we act, the less likely it will be to get out
into the community.”